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Abstract:

An actuating device for selecting fixed gear ratios of a gear shifting
transmission. The actuating device comprises a shift lever movable
between at least three gear positions, and a lockout mechanism for
limiting the range of motion of the shift lever. The lockout mechanism
comprises a locking assembly including at least one locking chamber
disposed in at least one locking roller, and the shift lever includes at
least one locking cam. The locking cam can be inserted into the locking
chamber to limit the range of motion of the shift lever. It is thus
possible to implement actuating and locking tasks in the field of
shift-by-wire transmissions, in a simple way and with minimal
construction space requirements. The actuating device produces minimal
noise and has short shifting times, and makes it shift-by-wire-controlled
H shift patterns possible.

Claims:

1-11. (canceled)

12. An actuating device for selecting a fixed gear ratio of a gear
shifting transmission, the actuating device comprising:a shift lever (1)
being movable between at least three gear positions, anda lockout
mechanism for limiting a range of motion of the shift lever (1), for
excluding certain shift lever positions, and blocking the shift lever
(1), the lockout mechanism comprises a locking chamber assembly that
includes at least one locking chamber (9) disposed in at least one
actuatorically rotatable locking roller (2, 3), and the shift lever (1)
includes at least one locking cam (7, 8), the locking cam (7, 8) being
engagable with the locking chamber assembly and inserted into the locking
chamber (9) for limiting the range of motion of the shift lever (1).

13. The actuating device according to claim 12, wherein the locking
chamber assembly of the at least one locking roller (2, 3) has a
plurality of locking chambers (9) that are adjacently disposed along a
rotational axis of the locking roller (2, 3).

14. The actuating device according to claim 12, wherein the lockout
mechanism has two actuatorically rotatable locking rollers (2, 3), and
the shift lever (1) has two locking cams (7, 8) that are situated
opposite one another relative to a shift lever axis, a first locking
chamber assembly of a first locking roller (2) is assigned to a first
locking cam (7), and a second locking chamber assembly of a second
locking roller (3) is assigned to a second locking cam (8).

15. The actuating device according to claim 12, wherein the shift lever
(1) is multi-stable.

16. The actuating device according to claim 12, wherein the at least one
locking roller (2, 3) is activated depending on speed of a vehicle
incorporating the actuating device.

17. The actuating device according to claim 12, wherein at least one of
the locking chambers (9) of the locking chamber assembly has a ramp-type
runout (14) toward a surface of the locking roller (2, 3), adjacent at
least one end thereof, so that the shift lever (1) is moved
actuatorically via rotation of the locking roller (2, 3) via the
ramp-type runout (14).

18. The actuating device according to claim 12, wherein the actuating
device has two locking rollers (2, 3) and the two locking rollers (2, 3)
are actuated by a common actuatoric drive (4).

19. The actuating device according to claim 18, wherein the two locking
rollers (2, 3) and the actuatoric drive (4) are coupled to one another
via a common toothed belt (5).

20. The actuating device according to claim 18, wherein the common
actuatoric drive is a servomotor (4).

21. The actuating device according to claim 12, wherein a rotational angle
sensor is disposed on the at least one locking roller (2, 3).

22. The actuating device according to claim 12, wherein a return spring
(13) is disposed on the at least one locking roller (2, 3).

23. An actuating device for selecting a fixed gear ratio of a gear
shifting transmission, the actuating device comprising:a shift lever (1)
comprising at least one locking cam (7, 8) and being shiftable between at
least three gear positions;a lockout mechanism for limiting a shifting
motion of the shift lever (1), the lockout mechanism comprising at least
one locking roller (2, 3) being rotationally actuatable, and at least one
locking channel (9) being located in the at least one locking roller (2,
3); andthe locking cam (7, 8) being insertable into the locking channel
(9) of the locking roller (2, 3) for limiting the shifting motion of the
shift lever (1).

[0002]The invention relates to an actuating device for a gear shifting
transmission, e.g. for an automated manual transmission having
shift-by-wire actuation.

BACKGROUND OF THE INVENTION

[0003]Gear shifting transmissions of motor vehicles are shifted or
controlled in general using an actuating device located within reach of
the driver. Actuating elements such as shift levers or selector levers
are used regularly for this purpose, and are located, for example between
the front seats of the motor vehicle or in other regions of the cockpit.

[0004]In the case of manually shifted transmissions in particular, purely
mechanical actuating devices and transfer means are often still used
between the actuating element and the gear shifting transmission. These
can be mechanical transfer elements such as cables or linkages, for
example, between the actuating element and the transmission. Newer manual
transmissions for passenger cars usually include five or six forward
gears and one reverse gear, wherein these six or seven gear positions of
the shift lever are disposed, in general, in the form of an H shift
pattern, grouped around a center, neutral middle position of the shift
lever.

[0005]An H shift pattern for a mechanically actuated manual transmission
often requires considerably more construction space for the actuating
system in the region of the vehicle interior, however, due to the
shifting travel and the selector travel required at the transmission, and
due to certain actuating forces on the shift lever that cannot be
exceeded for reasons of ergonomics, in particular compared to a selector
lever of an automatic transmission or to a shift-by-wire control for an
automatic transmission.

[0006]However, since different actuating systems must be provided for
various variants of a motor vehicle having different types of
transmissions, this means that the vehicle interior must therefore
likewise be adapted to the construction space required for the actuating
system, for example in the region of the center console, the cockpit, or
the floor panel, depending on the type of vehicle transmission and,
therefore, on the type of actuating system that is used. Therefore,
depending on the type of transmission that is used, or on the type of
actuating device that is used, this can result in the need to make
complex changes to the aforementioned assemblies in the region of the
vehicle interior, which is associated with correspondingly high costs. A
further disadvantage that can be associated with the mechanical transfer
of shift commands between the actuating device and the gear shifting
transmission of the motor vehicle lies in the need for the cables or
linkages to pass through the vehicle floor panel, the driveshaft tunnel,
or the bulkhead of the motor vehicle. These passages are likewise
structurally complex, and can also be disadvantageous in terms of noise
production, the transmission of structure borne noise, and crash
behavior.

[0007]Attempts have been made to circumvent these disadvantages, which
occur in the prior art, by converting gear shifting transmissions of
motor vehicles, including manual transmissions, to shift-by-wire
actuation. The purpose of this was to obtain greater design flexibility
in the vehicle interior in terms of the design and placement of the
actuating device for the transmission. Due to the elimination of
mechanical transmission linkage and spatially extensive mechanical
actuating levers, it is hereby also made possible to provide the most
uniform assemblies possible in the region of the cockpit, the floor
panel, and the center console for all variant transmissions of a motor
vehicle.

[0008]Even in the case of shift-by-wire actuating devices for motor
vehicle transmissions, however, it is necessary to provide the driver
with a realistic feel for the actuation of the transmission, for reasons
of safety and ergonomics. It is therefore necessary that the driver be
provided with visual feedback as well as clear haptic or tactile feedback
regarding the current shifting state or operating state of the
transmission when the transmission is actuated.

[0009]For reasons of ergonomics and safety, it is therefore particularly
important that the driver receive clear haptically noticeable signals
that certain shifting states or shift operations are not permitted at a
particular moment in the form of the corresponding operating positions of
the shift lever being blocked; the driver is already familiar with this
situation from the use of fully synchronized mechanical manual
transmissions, for example, with their rotational speed-dependent and
speed-dependent synchronizer locks.

[0010]However, when gear shifting transmissions are actuated electrically
or using shift-by-wire, the actuating element in the passenger
compartment and the motor vehicle transmission in the engine compartment
are not mechanically coupled in this manner. Instead, in the case of
"shift-by-wire" transmissions, the shift commands are transmitted from
the actuating device to the motor vehicle transmission using electrical
or electronic signals, and the shift commands are then usually
implemented at the transmission using electrohydraulics. Due to the
absence of a mechanical connection between the transmission actuator
system and the actuating lever, however, the transmission state, any
shift interlocks, or impermissible shift commands can no longer react
directly to the state of the actuating lever. Since certain gear
positions are not noticeably blocked at the actuating lever, the driver
of a vehicle equipped with a shift-by-wire transmission is unable to
easily recognize that certain lever positions, gear selections, or shift
commands may not be permitted in the current driving condition and
therefore cannot be selected.

[0011]Depending on the state of the gear shifting transmission to be
operated, and depending on other factors of the state of the motor
vehicle, e.g. engine speed, vehicle speed, clutch position, etc., in
order to implement the necessary haptic feedback in
shift-by-wire-controlled transmissions, it is generally necessary to
limit the range of operation of the actuating lever in an
actuator-controlled manner and depending on the transmission state. In
this manner, when the driver grasps the actuating lever, he can be
notified in a haptically noticeable manner, even when the vehicle is
equipped with a shift-by-wire-controlled transmission, that his shift
request is not permitted and is therefore blocked, for example due to the
current speed of the motor vehicle or due to a current operating state of
the gear shifting transmission. It is therefore possible to prevent shift
commands that cannot be implemented by the transmission at the moment,
and that are detected by the transmission electronic unit and are not
transmitted to the transmission from being engaged at the actuating
element since deviations between the actual transmission state and the
shift position that was engaged at the actuating element are not
permitted.

[0012]To this end, the driver of a vehicle equipped with a
shift-by-wire-controlled transmission must experience the same haptic
reaction he would if using a mechanically actuated transmission--a manual
transmission that includes transmission linkage, for example--when he
makes an actuation attempt, in which shifting of the individual gears is
blocked at the shift lever, in particular, depending on the speed. In
this manner, the shifting of gears that are not permitted at the moment,
or gear selections that cannot be shifted by the transmission at the
moment are ignored electronically, and in fact are prevented at the
actuating element using a mechanical lock even before actuation is
attempted.

[0013]As described in US 2006/0016287 A1 or DE 10 2005 033 510 A1, for
example, attempts have been made to implement locks of this type by
equipping actuating levers of shift-by-wire-controlled gear shifting
transmissions with a plurality of actuators or multiple-action actuators,
and with appropriate lever elements or transmission elements to
selectively block impermissible shift commands. These actuators and the
lever elements or transmission elements they control are shifted
depending on the vehicle state or transmission state to thereby limit the
overall range of motion of the actuating element in accordance with the
current drive state or transmission state.

[0014]However, if a plurality of different lever positions in different
combinations must be blocked using actuators, then, according to the
prior art, a complex locking mimicry is often required for this purpose.
This has unwanted consequences due to the complexity and costs involved.
Problems can also arise in terms of the available construction space in
the region of the actuating device, and in terms of energy consumption
and heat generation.

[0015]This applies in particular when the aim in terms of a shift-by-wire
actuating device is to implement an H shift pattern, for example, to
control an automated manual transmission. The latter is very difficult to
implement using the lockout mechanisms known from the prior art in
particular since an H shift pattern can include two and even up to four
adjacently disposed shift gates, in which shift positions must be blocked
or unblocked, depending on the state.

SUMMARY OF THE INVENTION

[0016]Proceeding from this background, the object of the present invention
is to create an actuating device having a lockout mechanism, in
particular for the electrical or electronic shift-by-wire actuation of a
gear shifting transmission, using which the stated disadvantages of the
prior art can be overcome. The lockout mechanism should have a simple
design, even when the locking logic is complex, and rapid shifting times,
a low susceptibility to interference, low energy consumption, and minimal
noise production should be attained. Furthermore, the actuating device
should require as little construction space as possible, and costs should
be reduced compared to the conventional mechanical transmission of shift
commands, and compared to the shift-by-wire actuating devices known from
the prior art.

[0017]Considered, at first on its own, in the known manner, the actuating
device according to the present invention includes a shift lever that can
be moved within at least one shift gate and has at least three gear
positions, and includes one lockout mechanism. The lockout mechanism is
used to controllably limit the range of motion of the shift lever, to
exclude certain shift lever positions, or to block the shift lever, in
particular depending on the gear state of the transmission or the driving
condition of the motor vehicle.

[0018]According to the invention, however, the actuating device is
characterized in that the lockout mechanism includes a locking chamber
assembly that includes at least one locking chamber and is disposed in at
least one actuatorically rotatable locking roller. In addition, the shift
lever includes at least one locking cam, wherein the locking cam can be
engaged with the locking chamber assembly when inserted into the locking
chamber and thereby enabling or limiting the motion of the shift lever,
in particular depending on the current effective depth of the locking
chamber.

[0019]Compared to the prior art, from which mainly actuating devices are
known that include either actuators having a plurality of operating
positions (such as double-acting electromagnets, for example), a
plurality of actuators, or complicated locking mimicry with various
transmission elements, it is finally possible, due to the locking roller
according to the invention, to greatly simplify the design of the
actuating device. Nevertheless, a great deal of freedom still exists in
regards to designing the desired ranges of motion or the number of shift
stages for the shift lever, which is limited only by the largely
unrestricted shaping of the locking chamber assembly in the locking
roller.

[0020]Due to the invention, the mechanical transmission of shift commands
from the actuating device to the transmission using cables or linkages
can therefore be replaced by the transmission of shift commands using
electronic means, in a largely universal manner for all types of
transmissions and for all types of actuating devices, while
simultaneously retaining the haptic sensation known from the mechanical
transmission of shift commands. This applies in particular for the haptic
feedback of the shift lever related to impermissible shift commands
outside of a certain window of relative rotational frequency or speed.

[0021]The invention therefore results in considerably greater freedom in
regards to the design and placement of the actuating device in the
vehicle interior or cockpit. Since the locking chamber assembly can be
designed largely without geometric restrictions, thereby making it
possible to define practically any range of motion having practically any
number of different shift positions for the shift lever. Furthermore, the
actuating device according to the invention can be adapted to the most
diverse vehicle transmissions or customer requirements simply by
replacing the locking roller, in the sense of a modular system, without
having to redesign the entire actuating device or the surrounding
assemblies in the motor vehicle. Due to the invention, decisive savings
in terms of cost and construction space are therefore made possible.

[0022]The invention can be implemented regardless of how the at least one
locking roller and the locking chamber assembly accommodated therein are
implemented, designed, and disposed, provided the intended interaction of
the locking chamber assembly with the at least one locking cam of the
shift lever is ensured. According to particularly preferred embodiments
of the invention, however, the locking chamber assembly of the at least
one locking roller includes a plurality of locking chambers that are
adjacently disposed along the rotational axis of the locking roller.

[0023]Furthermore, the actuating device preferably includes not one but
two actuatorically rotatable locking rollers, and the shift lever
includes two locking cams that are situated opposite one another relative
to the shift lever axis. The locking chamber assembly of the first
locking roller is assigned to the first locking cam of the shift lever,
and the locking chamber assembly of the second locking roller is assigned
to the second locking cam of the shift lever. In this manner, motions of
the shift lever that start from a center position and continue forward or
backward relative to the direction of travel can be controlled and
blocked using actuators.

[0024]The shift lever is preferably a multistable shift lever that, in
contrast to a monostable shift lever, basically remains in each of its
gear positions once it is released after actuation. Due to a plurality of
locking chambers which are adjacently disposed along the rotational axis,
and due to two actuatorically rotatable locking rollers, complete shift
patterns of mechanical selector levers or shift levers can therefore
likewise be implemented in entirety with a shift-by-wire actuation, in
particular when a multistable shift lever is used.

[0025]Due to the embodiment of the actuating device according to the
invention, which includes two locking rollers, each of which includes a
plurality of adjacently disposed locking chambers, it is possible in
particular to replicate and realistically simulate the entire H shift
pattern of the shift lever of a manually actuated transmission. For this
purpose, a separate locking chamber is provided on each of the two
locking rollers, for each of the up to four adjacently disposed shift
gates of a typical H shift pattern which includes five to six forward
gears and one reverse gear. In this manner, the particular permissible
ranges of motion can be defined and controlled separately for each of the
e.g. four shift gates of the H shift pattern by assigning a pair of
associated locking chambers on the two locking rollers to each shift
gate.

[0026]The driver is very familiar with the principle of the conventional H
shift pattern due to previous experience with mechanical actuation of
manual transmissions; due to the invention, this principle can be
transferred to the field of shift-by-wire controls, thereby largely
ruling out misuse of a shift-by-wire-controlled manual transmission due
to the H shift pattern according to the invention.

[0027]According to a particularly preferred embodiment of the invention,
the at least one, preferably two locking roller(s) is/are actuated
depending on the vehicle speed. This embodiment also serves to implement,
as completely as possible, the H shift pattern with which the driver is
familiar in a shift-by-wire-controlled gear shifting transmission, such
as a by-wire-controlled double clutch transmission or an
electrohydraulically actuated manual transmission.

[0028]According to a further preferred embodiment of the invention, at
least one of the locking chambers, and preferably all of the locking
chambers of the actuating device, includes, on at least one of its ends,
a ramp-type runout that extends to the surface of the locking roller. In
this manner, the shift lever can also be returned to the center or
neutral position in a reliable manner using actuators, with the least
effort possible and by utilizing the design of the locking roller for two
purposes. As a result--in the case of manually shifted automatic
transmissions in particular--a transmission control can be realized in
which the transmission is automatically shifted to the parking lock
(Auto-P) when the motor vehicle is shut off or left, regardless of which
gear had actually been selected at the transmission control, in order to
prevent the parked vehicle from rolling away.

[0029]Due to this embodiment, according to which the shift lever is
returned to the center or neutral position using actuators, it can be
prevented that the shift lever is located in a position that does not
coincide with the "parking lock" transmission state the next time an
attempt is made to drive the vehicle.

[0030]If the shift lever were left in one of the gear positions when
leaving the vehicle, then, if Auto-P were engaged, the shift lever
position would not coincide with the actual gear state of the
transmission (parking lock) the next time the vehicle is started. Upon
returning to the vehicle or attempt to start the vehicle, the position of
the shift lever that the driver would observe, would provide him with
incorrect information. On the basis of his observation of the shift lever
position, the driver would have to assume that the transmission is
engaged in a gear selection position, although the transmission is
actually engaged in the parking lock.

[0031]To prevent the driver from being misinformed in this manner, an
additional signal device would therefore have to be provided especially
for the driver, that would, if the parking lock had been engaged by
Auto-P, signal to the driver that the shift lever must first be moved
manually into the center or neutral position before the vehicle can be
started. A signal device of this type is not necessary, however, due to
this embodiment of the invention and the actuatoric return of the shift
lever according thereto.

[0032]The embodiment of the invention that includes two locking rollers
and two locking cams can be implemented at this time regardless of how
the actuatoric drive of the two locking rollers takes place. For example,
the two locking rollers can each include a separate actuatoric drive, or
they can be coupled via gears. According to a particularly preferred
embodiment of the invention, however, the actuating device is
characterized by one common actuatoric drive for the two locking rollers.
Preferably, the two locking rollers and the actuatoric drive that is
common to the two locking rollers are coupled to one another by a toothed
belt, wherein the common actuatoric drive of the two locking rollers is
preferably formed by a servomotor.

[0033]These embodiments make possible a cost-saving design of the
actuating device having only one single electric motor actuator that can
nevertheless activate all different actuating locks of the shift
lever--in the various shift tracks of an H shift pattern, for example--in
a targeted manner.

[0034]According to a further preferred embodiment of the invention, a
rotation angle sensor is provided disposed on at least one locking
roller. This makes it possible to drive and reliably adjust the rotation
angle position, which is required for the particular lock, of the locking
roller or locking rollers even using a relatively simple electric motor
that can therefore function without the use of a separate sensor system.

[0035]According to a further preferred embodiment of the invention, it is
furthermore provided that a return spring is disposed on at least one
locking roller. The return spring, which can be designed e.g. in the form
of a flat spiral spring, makes it possible to actuate the shift lever in
particular even if the actuator drive of the locking rollers should fail,
or after the ignition is shut off. In this case, the locking rollers are
rotated back, using the energy stored in the return spring, to a
predetermined position in which all actuating positions of the shift
lever can be selected.

BRIEF DESCRIPTION OF THE DRAWINGS

[0036]The invention is explained below in greater detail with reference to
drawings that merely depict examples of embodiments. They show:

[0037]FIG. 1 in a schematic, isometric view, the lockout mechanism of an
embodiment of an actuating device according to the present invention, in
a view looking upon the toothed-belt drive;

[0038]FIG. 2 the lockout mechanism according to FIG. 1, in a depiction
that corresponds to FIG. 1, in a view looking upon the locking rollers
and actuator drive;

[0039]FIG. 3 the lockout mechanism according to FIG. 2, in a depiction
that corresponds to FIG. 2, with the shift lever deflected and the
locking cam plunged into locking chamber;

[0040]FIG. 4 in a schematic, partial cross sectional side view, the
lockout mechanism according to FIGS. 2 and 3, with the shift lever
deflected as in FIG. 3;

[0041]FIG. 5 in a schematic, isometric view, the locking roller at the
rear, relative to the direction of travel;

[0042]FIG. 6 in a depiction and view that correspond to FIG. 5, the
locking roller at the front, relative to the direction of travel, with
return spring; and

[0043]FIG. 7 the assignment table of the locking chambers for the locking
rollers according to FIGS. 5 and 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044]FIG. 1 shows, in a schematic, isometric view, the lockout mechanism
for an embodiment of an actuating device according to the present
invention, in a view looking upon the toothed-belt drive. The
illustration clearly shows (only partially, for reasons of space) shift
lever 1, locking rollers 2 and 3, and electric motor drive 4 and its
toothed-belt drive 5 for controlling the rotation of locking rollers 2
and 3. Direction arrow 6 indicates the direction of travel of the motor
vehicle that applies for this embodiment.

[0045]FIG. 2 shows the situation according to FIG. 1 from the opposite
viewing direction, looking upon locking rollers 2, 3 and electric motor
4. FIG. 2 shows, in particular, locking cams 7, 8 which are disposed on
shift lever 1 and, in this embodiment, are formed as a single piece with
shift lever 1. Locking cams 7, 8 are disposed such that they are inserted
into corresponding locking chambers 9 of locking rollers 2, 3 when shift
lever 1 is swivelled.

[0046]Depending on the rotational angle position of locking rollers 2,
3--wherein the rotation angle position is controlled by servoactuator 4
via toothed-belt drive 5--a different arrangement of locking chambers 9
affects locking cams 7, 8, thereby enabling the corresponding shift
motions of shift lever 1 to be released or blocked depending on the
rotational angle position of locking rollers 2, 3.

[0047]FIG. 2 also clearly shows notched gate 10 and interlock pin 11 which
is guided into notched gate 10 and is axially spring-loaded. Notched gate
10 and interlock pin 11 are used for defined guidance and to produce the
locking forces and restoring forces required for reasons of ergonomics
and shift logic, when shift lever 1 is moved.

[0048]FIGS. 3 and 4 show locking cams 7, 8 inserted into corresponding
locking chambers 9 of locking rollers 2, 3. FIGS. 3 and 4 clearly show
shift lever 1 which has been swiveled forward relative to direction of
travel 6. When shift lever 1 is swiveled, locking cam 8 is likewise
swiveled, and inserts into one of the locking chambers 9 of the
rear--relative to the direction of travel--locking roller 3, provided the
latter is located in an appropriate rotation angle position.

[0049]However, if the swivelling motion of shift lever 1 depicted in FIGS.
3 and 4 should be prevented or blocked in a manner that is noticeable to
the driver--since, e.g. the vehicle speed or the relative rotational
frequency in the transmission are not suitable for the particular shift
command--actuator drive 4 is activated by the transmission electronic
system in a manner such that no locking chamber 9, into which locking cam
8 could be inserted, is located opposite locking cam 8. In this case,
when an attempt is made to actuate shift lever 1 accordingly, locking cam
8 strikes smooth surface 12 of locking roller 3. As a result, the driver
receives a clear haptic signal that the shift lever cannot be moved in
the intended direction at this time since this would correspond to a
shift command that is impermissible at the moment (e.g. shifting into
second gear when the vehicle is traveling at a high rate of speed, or
shifting into reverse while the vehicle has not stopped).

[0050]When shift lever 1 is moved laterally, transversely to the direction
of travel, different pairs of locking chambers 9 of locking rollers 2, 3
are located opposite each of the locking cams 7, 8 of shift lever 1. In
this manner, different shift positions can be permitted or blocked--in
particular, depending on the driving speed--for the different shift gates
of shift lever 1 without having to move locking rollers 2, 3 into a
different rotational angle position every time shift lever 1 is moved
into a different shift gate.

[0051]FIG. 4 clearly shows, once more, the action of locking cam 8
inserted into one of the locking chambers 9 of locking roller 3,
according to FIG. 3, at the rear relative to the direction of travel.
Furthermore, FIG. 4 also shows notched gate 10 and interlock pin 11 which
slides in notched gate 10 and is movable in shift lever 1 under axial
spring loading. Furthermore, a possible embodiment of the ramp-type
runout of locking chamber 9 is indicated schematically in FIG. 4 using
dashed line 14. Using ramp 14, which can have a spiral shape, for
example, shift lever 1 can be moved back into its center position shown
in FIGS. 1 and 2 via actuator-controlled rotation of locking roller 4.

[0052]FIGS. 5 and 6 show locking rollers 3 and 2 once more, in an enlarged
view. It is clearly shown that locking roller 2 is provided with a spiral
return spring 13. Return spring 13 is preloaded by electric motor drive 4
of locking rollers 2 and 3 and is used, e.g. if the system should fail,
to automatically return locking rollers 2, 3 into the home position, in
which all shift positions of shift lever 1 can be selected since, in the
home position of the locking rollers 2, 3, a corresponding locking
chamber 9 is available for locking cams 7, 8 for every shift position of
shift lever 1.

[0053]This home position of locking rollers 2, 3 corresponds to the row
marked with an "X" in the table shown in FIG. 7. The column headers "R 1
3 5-2 4 6" of the table shown in FIG. 7 represent the assignment of the
individual gear stages that can be selected using shift lever 1 to
particular locking chambers 9 which are disposed on associated locking
rollers 3 and 2. The row headers between "0" and ">130" stand for the
ranges of vehicle speed at which actuator 4 moves locking rollers 3 (left
half of the table) and 2 (right half of the table) into the particular
associated rotational angle position.

[0054]The table makes clear that reverse gear and first gear can be
engaged e.g. when the vehicle is at a standstill, while all other gear
positions are blocked. At a speed between 50 and 60 km/h, this embodiment
can select all gears except for reverse gear and sixth gear, and, at
speeds above 130 km/h, only the fifth or sixth gear can be selected,
while all other gears are blocked by locking cams 7, 8 striking smooth
surfaces 12 of locking rollers 2, 3 outside of locking chambers 9. In
home position "X", into which the two locking rollers automatically move
due to return spring 13 e.g. if drive 4 fails, a locking chamber 9 is
provided in both locking rollers for every shift position of shift lever
1, thereby making it possible for all shift positions to be selected in
home position "X".

[0055]The ranges of vehicle speeds in which certain shift operations are
permitted and others are excluded can be easily adapted to corresponding
vehicle variants or customer preferences by making appropriate changes to
locking rollers 2, 3.

[0056]In summary, it is therefore clear that with the invention, an
actuating device is created that includes the particular advantage over
the prior art that it functions using a relatively simple design, even
when blocking tasks are complex. Substantial advantages are attained in
the form of minimizing the amount of construction space required, low
noise production and in the form of short shifting times coupled with a
low susceptibility to interference. When H shift patterns are involved in
particular, cost savings and structural advantages are attained compared
to the mechanical transmission of shift commands, and compared to the
shift-by-wire actuating devices known from the prior art. The driver is
provided with reliable tactile feedback about the actual gear state and
the current permissible shift commands.

[0057]Due in particular to the simple, modularizable design, the invention
therefore makes a central contribution toward increasing cost
effectiveness across all model series, and toward improving the
ergonomics and safety of actuating devices for motor vehicle
transmissions.